a. Field of the Invention
The instant invention relates to catheters that are used in the human body. In particular, the instant invention relates to an irrigated catheter utilizing multi-lumenal irrigation tubing to provide multiple dedicated and/or independent irrigation flows. The present invention also relates to methods of manufacturing and using such a catheter.
b. Background Art
Catheters are used for an ever-growing number of procedures. For example, catheters are used for diagnostic, therapeutic, and ablative procedures, to name just a few examples. Typically, the catheter is manipulated through the patient's vasculature and to the intended site, for example a site within the patient's heart.
A typical electrophysiology catheter includes an elongate shaft and one or more electrodes on the distal end of the shaft. The electrodes may be used for ablation, diagnosis, or the like. Electrophysiology catheters also often include irrigation, for example, to provide a conduction pathway to carry ablative energy to nearby tissue and/or to cool nearby tissue to prevent excessive thermal damage such as charring.
Extant irrigated catheters often exhibit certain disadvantages. For example, in an irrigated catheter that includes a pressure-driven irrigation flow, if an irrigation passageway becomes obstructed, the irrigation fluid will seek lower pressure outlets and redistribute to other irrigation passageways, leading to a situation where certain areas of the catheter are not irrigated to the extent desired. As another example, in an irrigated catheter that includes a volume-driven irrigation flow, if an irrigation passageway becomes plugged, the volume-driven pump will push to open the passageway (that is, the same volume of irrigation fluid will be delivered to the occluded passageway, regardless of the pressure necessary to do so).
These shortcomings may be ameliorated by creating multiple independent irrigation flows. This solution, however, presents its own shortcomings. One way in which multiple independent irrigation flows is to employ multiple saline bags, with one bag dedicated to each irrigation flow. Saline bags, however, are not ideal for delivering accurate, consistent, and predictable irrigation flows. To overcome these disadvantages associated with saline bags, an irrigation or infusion pump may be employed, but it is not economical to utilize multiple such pumps to provide multiple irrigation flows.